Dynamo-electric machine.



. wit" oeo No. 883,043. PATENTBD MAR. 24, 1908.

' J. P. NIKONOW.

DYNAMO ELECTRIC M ACHINB.

APPLICATION FILED APR.13,1907.

2 SHEETS-SKEET l.

17 9 avwudor e/adu ll'lVi lam/v ,PATENTED MAR. 24; 1908.

3. P. NIKONOW.

DYNAMO ELECTRIC MACHINE.

APPLICATION FILED APR. 13, 1907.

2 smms smm 2.

attowwqo UNITED STATES PATENT OFFICE.

JOHN l. NIKUNUW, Ul" l lTSBlJRG, .llJNNdYLVANI L I I v DYNAMIC-ELECTRIC MACHINE.

No. 883,043. Specification of Letters Patent. Patented March 24, 1903. Application filed April 13, 1907. Serial No. 368,029.

To all whom it may com'cru: I one of the poles. Fig. 6 represents by means Be it known that l. Jonx l. Xnioxon', a l ol'curves the intensitv ol' thciicld mid armasubject oi the Czar of Russia. residing at ture fluxes and also of the reluctant flux.

Pittsburg, in the county of Allegheny and i Fig. 7 shows a modification for compound State of Pennsylvimia, have invented certain wound machines.

new and useful Improvements in Dynamol (oi-responding and like parts are referred Electric Machines, of which the following is a l to in the following description and indicated specification. I in. all the views of the drawings by the same The present invention relates to an im- 1 reference kllfil'ilCltl'S. proved field construction for dynamo electric I T he invention is shown as applied to 9. machines, such as direct current motors, dyl multi-polar nmrhine and in. the preferred emnamos, revolving field alternators and synbodiment shown in Figs. 1 and 2 the field chronous motors. construction ol the machine comprises a 1n the operation of dynamos considerable main or intermediate yoke 1 which is in the 7g difiiculty is frequently encountered in obnature of a continuous ring and carries the tainmg a good commutation and maintaininwardly extending and radially disposed ing a constant electromotivc force owing to cores 2. The armature 3 is mounted in the the distortion of the field flux by the armausual manner so as to rotate between the inture flux induced by the current flowing ner extremities of the cores 2. Located upon through the armature leads or inductors. each side of the cores 2 are supplemental v The object of this invention has been to cores 4 and 5, the corresponding supplemenobviate this dilliculty by reducing this artal cores of each pole being counteracted bv mature reaction to a minimum, and this rea separate yoke member whereby a series of suit is accomplished by the provision of a independent magnetic circuits is produced 3() novel field construction in which the various within each pole. As shown in the drawings poles comprise a series of cores, each core the supplemental cores 4 are magnetically orming a part of an independent magnetic connected to arms 6 projecting inwardly circuit. With this construction a series of from the yoke member 7 which is in the naair gaps are introduced into the path of the ture of a ring secured to one side oi the main 5 armature flux andthe reluctance of the said yoke l by means of the bolts 8 and n1cgnetpaths is increased to such an extent as to ically insulated therefrom. A similar yoke effectively split up the armature flux into a member 9 is secured to the opposite side of plurality of comparatively small and local the main yoke l and is-i'ormed with the incircuits which do not distort the field flux to .wardly extending arms 6 which are magnetany marked extent. ically connected with the supplemental cores For a full description of the inventionand 5. These two yoke n'icmbers 7 and 9 are the merits thereof and also to acquire a held spaced from the main yoke 1 by means knowledge of the details of construction and of insulating washers 10, whereby an air gap the means for efiecting the result, reference is produced between the various yoke pieces is to be had to the following description and of the field construction. It found desirable accompanying drawings, in which: the yoke-members 7 and 9 may as in the Figure 1 is a side elevation of the upper present instance be formed with the spiders portion of the dynamo electric machine con- 11 having the bearings 12 located at their structed in accordance with the present in central portions within which the armature 00 vention. Fig. 1 is' a similar view of the shaft 15 ournaled. The several cores of each lower portion of a machine embodying a field pole are magnetically insulated from modification of t-he invention. Fig. 2 is a each other and this rcsult may he accomtransverse vertical sectional view through plished either by means of the washers 13 or the upperportion of a machine embodying by filling blocks 14 of some non-magnetic the invention. Fig. 2 is a similar view material. The exciting field coil 15 of each throughthc lower portion of a machine and ole is wound about the several cores colshows a modification. Fig. 3 is a side eleva-' ectively so that when the exciting current tion. of a portion of a machine. Fig. 4 is a is passed through the coil independent mags view showing the invention as applied to a ne-tic circuits are produced in the various 11o revolving field. Fig. 5 is a diagrammatic} cores.

view showing the magnetic circuits under As indicated by the dotted line as in Fig. l

the path followed by the flux produced by the action of the field coils upon the main cores 2 extends from one of the cores 2 across the air gap into the body of the-armature, through the body of the armature, across the second air gap into the opposite core 2, and

through the main yoke 1 into the first men tioned core 2. In a similar manner the path of the flux-produced by the auxiliary cores 4 and indicated by the dotted line 1 can be traced through the armature and the pole 23.6065 6 and through the yoke member 7.

- ihe path of the flux roduced by the auxtend throughout the entire ole and thereby distort the main flux. In t is figure thearmature'leads or inductors 16 are shown as located under one of the pole pieces and the circuits of the armature flux are indicated by the dotted lines17. The effect of the armature flux upon the main flux is indicated diagrammatically in Fig. 6 wherein the line AB represents the armature surface in one pole division between two neutral lines, while the ordinates represent the fiux density at the respective points. The curve 18 is derived from the armature flux and the curve 19 from the field fiux., By combining these two curves I obtain the curve 20 which re resents the resultant distribution of theux.

From a study ofthese curves it will be apparent that while there are slight variations in flux density for each of the cores, yet the variation for the whole pole is considerably less than would be the casewere the core one solid piece as in the usual construction.

A modification is shown in Figs. 2 and 1 in which the yoke of the machine comprises a pair of spaced rings 21, and the field oles are each formed of a pair of magnetica ly insulated cores 22 carried by or magnetically connected to arms 23 projecting from the res'pective yokes 21. Inthe present instance the two yokes 21 are connected by a number of bolts and held spaced from each other by means of washers 24 surrounding the bolts. With this construction a two path field is produced instead of the three path field as in the former instance and two distinct magnetic circuits can. be traced through each of the pole pieces. With compound wound maclnnes as indicated in Fig. 7 it may be found desirable to restrict the series winding to one of the cores 22 as indicated'at 25 and thereby reinforce. the field on that side whereit is most distorted by the armature flux, While the main field winding as indicated at 26 the outer ends of the pole pieces inwardly and holding them firmly against the arms carried extends around the two cores 22 collectively. Under some conditions it may be found desirable to employ jack screws 27 for forcin by the yoke members.

This invention also has the advantage of reducing the field leakage and of enabling the pole pieces of a multi-polar machine to be Y laced closely to other, since the lines of oree do not flow groin the adjacent side of one pole piece to the adjacent side of the next pole piece but from the far side of one pole piece to the adjacent side of the next pole central core 2 of the field poles laminated construction. These laminations have the general direction of the armature shaft so as to extend transversely across the ath of the armature flux and increase the re uctance of the said path. This is due to the thin films of air between the various laminations which constitute air gaps.

In Fig. 4 the principle of the invention is shown as applied to a revolving field and comprising magnetically insulated members 28 and 29 mounted upon the shaft-32 so as to rotate therewith in the usual manner. These members 28 and 29 carry the corres onding andradial arms 30 and 31 res ective y which form the cores around which t e exciting coils of the field are wound. The core of each of the field piles comprises a pair of the arms 30 and 31 w ch are spaced or magnetically insulated from each other so as to provide two distinct paths for the field flux. This construction operates in a manner identical with that previously described to break u the armature flux into a lurality of smal circuits, thereby preventing the same from distorting the main flux to such a marked degree as would otherwise be the case.

Having thus described the invention, what is claimed as new is:

1. A dynamo electric machinecomprising a plurality of poles each formed of a series of cores constituting parts of distinct magnetic circuits, the cores being arranged to cause the magnetic circuits to flow from the far side of 1one pole to the adjacent side of the next 2. A field construction for dynamo electric \machines comprising a series (if magnetically one pole to the adjacent side of the next pole.

3. A field construction'for dynamo electric machines comprising a plurality of magneticall insulated okes in the form of rings, and po es carried" y the yokes, each pole-con prising a plurality of magnetically insulated cores connected to the respective yokes, the

cores of each pole being arranged to cause the magnetic circuits to flow from the far side of one pole to the adjacent side of the next'pol'e. 4. A field construction for dynamo electric machines comprising -a main yoke, cores carried by the main yoke, a yoke member located upon each side of the main yoke and magnetically insulated therefrom, and auxiliary cores located upon opposite sides of the before mentioned cores and magnetically connected to the respective yoke members.

5. A field construction for compound wound dynamo electric machines comprising poles formed of a plurality of core pieces each iaving an independent magnetic circuit, the

series winding being limite to a selected one of the cores while the main winding surrounds the several cores collectively.

6. A field construction for compound wound dynamo electric machines comprising a series of magnetically separated yokes, and pole pieces magnetically connected to the various yokes, each pole comprising a plurality of core pieces each forming part of an independent magnetic circuit, the series winding being confined to a selected one of the cores of each pole, while the main winding surrounds the cores collectively. In testimony whereof I allix my signature in presence of two witnesses.

JOHN P. NIKONOW. [-L. Witnesses:

VERYL BROUGHTON, BIRNEY I'IINES. 

